Use and Care Guide

Unlike HID lamps and Incandescent/Halogen lamps which are
designed for optimum performance at a specific wattage, linear
fluorescent lamps can be operated over a reasonably wide range
without sacrificing performance, such as life or efficacy. Therefore,
there is no “optimum” wattage for a lamp, only a range. The F32T8
lamp can produce between 60% to 118% of its catalog lumens when
operated on a ballast with a ballast factor of 0.60 to 1.18. The higher
the operating wattage, the higher the lumen output within this range.
Consumers have a choice among ballasts, depending on how much
light they desire from the lamp and how much energy they are trying
to save. The ballast specification from the ballast manufacturer pro-
vides the “input wattage” of the ballast. A two lamp electronic ballast
with input watts of 56 watts (BF of 0.88) is using 56 watts of power to
operate 2 lamps--typically 26 watts in each lamp and 4 watts in the
ballast. In contrast, a ballast with BF of 1.18 will consume 76 watts
but also produce more light.
An engineer or designer will choose a high BF when trying to
“squeeze” as much light as possible from the lamp, e.g. in high-bay
applications or when they are trying to reduce the number of lamps
used in the area. A lower BF reduces the light output and wattage
of each lamp, so that more lamps (and more fixtures) are needed to
achieve a certain footcandle level in the same area. Of course more
fixtures also means closer spacing and more uniform lighting.
It must be noted that ballast factor (and any measure involving BF)
requires a measurement of lamp lumens and is, therefore, not a pure
electrical measurement. The uncertainty and variation associated
with individual lamp performance is present in these measures.
Actual Light Output of Lamp = (Catalog Lumens) x (Ballast Factor)
0.60
0.71
0.77
0.87
1.00
1.18
Light Output
XL
L low
L Low
N Normal
N+
H High
System Watts
Ballast Factor
Instant Start vs. Rapid Start Sockets
When using programmed start or dimming ballasts in fixtures,
sockets must be 2-pin rapid start type. Fixtures with T8 instant start
ballasts must use jumpered rapid start sockets or shunted lamp
holders (internal to the lamp holder) that bridge the lamp bi-pins
together into one contact on each side of the lamp. If retrofitting
from a instant start ballast fixture with shunted sockets to a
dimming or programmed start ballast, rapid start type sockets
must be used to properly start lamps and maintain rated lamp life.
GE Ballast Electronic nomenclature
GE-2 32-MVPS-N-42T
Maximum
number
of lamps
supported
by this ballast
– 1, 2, 3, 4, 6
IS = Instant Start,
standard if not shown
RS = Rapid Start
PS = Program Start
120 = 120 volt
277 = 277 volt
MAX or MV =
120 – 277V
Lamp Watts
(Primary Lamp)
T8 = 32-four foot,
59-eight foot
T12 = 40-four foot,
60-eight foot
Ballast Factor
L =Low Power for
MAX savings
N = Normal for
New Fixtures
N+ = Normal -
High 1.0
H = High Power,
Hi-Light, Hi-Bay
GE Ballast
GE = LFL
GEC = CFL
Ultra-Hi Efficiency
84T, 42T, T = 840, 420 qty
OEM pallet packs
A, D, E, F = Can sizes
BES = Bottom exit with studs
SE = Dual – side & bottom exit
3W = 3 way mounting kit
Understanding
Fluorescent Systems
GE introduced the first practical fluorescent lamp in 1938. All
fluorescent lamps operate on electrical control gear called a ballast.
Today, electronic ballasts have continued to replace the magnetic
designs that were common previously. The 4-foot T8 lamp on an
electronic ballast is the most common system. The generic version
of this lamp is called the F32T8 and in recent years, energy saving
reduced wattage lamps like the F28T8 and the F32T8/25W have
become popular. These lamps typically operate on Instant Start (IS) or
Programmed Rapid Start (PRS) ballasts and both types of ballasts are
available in a variety of ballast factors ranging from 0.60 to 1.18.
Ballast Factor
The F32T8 lamp has a “nominal” wattage of 32 watts. Nominal means “in
name only” because there are no ballasts commercially available that will
operate this lamp at 32 watts! The “N” or “Normal” ballast
factor ballast operates this at around 26 watts while the “L” operates the
lamp around 23 watts; the “N+” operates it around 29 watts and the “H”
around 34 watts. Electronic ballasts operate lamps at high
frequencies of greater than 20 kHz, which results in more efficient lamp
operation than at 60 kHz, like the magnetic ballasts they replace. This
results in a lamp that is more efficient than the 32 nominal watts.